Workers have started bulldozing the Calais "Jungle" camp as thousands of migrants and refugees were taken by bus to their new homes.

Heavy duty machinery was brought in on Tuesday afternoon as the mass exodus of the camp continued into its second day.

A small yellow bulldozer could be seen crushing the structures and lifting debris into a large skip on the edge of the camp.

Dozens of workers in orange jumpsuits and white helmets helped by dumping the pallets, fabric and plastics which once housed migrants into the industrial container.

French police step in break up clashes in the 'Jungle' camp Photo: John Stillwell/PA Wire

A group of migrants huddled together in silence as workers tore down a nearby blue and yellow patterned shelter which was decorated inside by blankets.

A world atlas lay abandoned on a battered brown chair 2ft away from the demolition work.

Dorothy Sang, working on the ground for Save the Children, said the camp was being made even more dangerous by demolition starting before everyone had left.

She told the Press Association: "It is unacceptable that the demolition has just started while those children haven't been put to a safe place or accounted for.

"We know from the last time the camp was demolished that this escalates very quickly.

"This is not a safe environment for children - particularly children on their own."

A coloured bracelet is placed on the wrist of a migrant at the start of their evacuation and transfer to reception centers in France, and the dismantlement of the camp called the "Jungle" in Calais, France, October 24, 2016. REUTERS/Philippe Wojazer

Earlier, scuffles broke out in the camp less than an hour after French authorities began a second round of processing refugees and migrants for relocation to other parts of the country.

Some 16 buses transported 656 migrants to six regions in France on Tuesday morning, the French interior ministry said, while 139 minors were also processed.

Since Monday, more than 3,000 migrants and refugees have passed through the registration centre.

Elsewhere in the camp the once-bustling main thoroughfare was quiet, with most of the shops and restaurants abandoned.

The earlier spat is thought to have started as unaccompanied minors were being separated from the main queue and taken to the front.

Someone shouted into a loudspeaker: "Sit down, the door is closed. Stop pushing," while cries of "Help, please help" were heard as people started to panic.

Migrants and refugees believed to be minors could be seen crouching down by metal barriers while police formed a protective circle around them.

Save the Children said it was "very concerned" about the way in which minors were being registered.

Ms Sang said: "The children have waited for months and months and now at the final hurdle it feels like this process is just really not working for them in their best interests."

Migrants carry their belongings as they board a bus at the start of their evacuation and transfer to reception centers in France, and the dismantlement of the camp called the "Jungle" in Calais, France, October 24, 2016. REUTERS/Philippe Wojazer

An aid worker for the Care4Calais charity on the ground said she had seen police rip a scarf off a migrant's face to judge how old he was.

Numbers are expected to be fewer than on Monday, when hundreds of camp residents with holdalls, rucksacks and wheeled bags queued up in the dark more than an hour before the registration centre opened.

Many migrants were studying sheets of paper given to them by aid workers which included information in Arabic and English and a map of France.

Buses will arrive every day until they are no longer needed, it is understood, with officials saying the entire operation will last at least a week.

On Tuesday 1,636 people, including 372 minors, passed through the registration centre, bringing the total number over two days to over 4,000.

Some 1,264 adult migrants and refugees were taken by 33 buses to 55 accommodation centres in nine regions across France, the French Interior ministry said.

At least 772 unaccompanied minors have been identified during the two days, while 217 minors with family in Britain have come to the UK since October 17, it added.